Telephone system



Sept. 7, 1937. R. H. J. SCHOEPPE 2,092,360

TELEPHONE SYSTEM File d June 5, 1956 2 Sheets-Sheet l Inventbr Attorneys se g. 7, 1937.;

R. H. J. SCHOEPPE TELEPHONE SYSTEM 2 Sheets-Sheet 2 Filed June 5, 1956 By 2am M m A tiome us Patented Sept. 7, 1937 UNITED STATES. PATENT OFFICE 2,092,360 TELEPHONE SYSTEM Richard H. J. Sohoeppe, Baltimore, Md. Application June 5, 1936, Serial No. 83,782

2 Claims.

This invention is a signalling device for use in conjunction with telephone systems to insure privacy in conversation.

An object of the present invention is to provide a signalling device of this character which while it is usable in conjunction with party-line magnetic means and the switches being arranged in a battery circuit separate and distinct from the telephone circuit so as to operate entirely independently thereof; the arrangement beingsuch that, with any two persons conversing through the medium of two of the telephones or subscriber sets in the system, and a third person should remove the hook from the receiver of a third telephone or subscriber set in the telephone system, the circuit forming a part of the signal apparatus will be completed in a manner to causea shifting of the signal elements associated with each of the three telephones or subscriber sets to the end that the two original parties engaged in conversation will be immediately apprised of the fact that a third party is either listening in or is desirous of using his (the third partys) telephone.

The invention together with its objects and advantages will be best understood from a study of the following description taken in connection with the accompanying drawings wherein:-

Figure 1 is an elevational view of a telephone subscriber set of the type used in inter-office telephone communication systems and showing the position of the indicator when the ear phone is in position on the hook of the set.

Figure 2 is a view somewhat similar to Figure 1 and showing the position of the indicator when the ear phone has been removed from the hook.

Figure 3 is a rear elevational view of the set.

Figure 4 is a sectional view taken substantially on the line 4-4 of Figure 3.

Figure 5 is a perspective view of a hook embodying the features of the present invention.

Figure 6 is a perspective View of a slide forming one form of the invention.

Figure 7 is a view somewhat similar to Figure 2 5 and illustrating a slightly modified form of the invention.

Figure 8 is a perspective view of a slide forming part of the modified form of the invention and l 10 liigure 9 is a wiring diagram of the signal circui Referring to the drawings by reference numerals it will be seen that there is provided for each telephone set indicated generally by the 15,

reference numeral 5 a signalling device which in the form of the invention shown in Figures 1 to 6 inclusive comprises a casing 6 formed integrally with or otherwise secured to the top wall of the casing of the subscriber set. At the front side thereof the signal casing 6 is provided with a sight window 1.

Having a sliding fit in the casing 6 is a slide plate 8 on which, in this form of the invention, is suitable legendary matter such as, for example, Not private and fPrivate disposed under the legend Not private.

The slide plate 8 forms on one end of a rod 9 in any suitable manner preferably by being integral withthe rod.

The rod 9 extends downwardly into the easing of the set 5 and at its lower end is connected with an armature I0 pivotally mounted on and insulated from a wall of the casing of the set 5 as atv II. The armature I0 is 35 normally urged upwardly through the medium of a spring l2 sothat the legend Private isnormally disposed opposite the sight window 1 as shown in Figure 1.

Also mounted on and insulated from the wall of the casing of the set 5 is a bracket l3 which supports in operative position to the armature l0 an electro-magnet l4.

Also suitably mounted within the casing of the set 5 and insulated from the casing as at l5 are a pair of springs which contact l6 and I! respectively. (See Figure 3.)

The hook of the set 5 is indicated by the reference numeral l8 and at its pivoted end |8a;, internally of the casing of the set 5, the hook I8 is 50 provided with an angular arm l9 which has an offset end upon which is sleeved rubber or other suitable insulating material 20. The rubber equipped end as shown in Figure 3 is arranged in operative position to the contacts l6 and I! so that when the ear phone 2| is removed from the hook l8 and said hook swings upwardly contact I! will be forced into electrical engagement with the contact l6.

In Figure 9 there is illustrated the application of the invention to a system involving three telephones. It will thus be seen that when the ear phones 2| of any two of the set have been removed from their hooks ill the signal circuit will not be completed due to the fact that while the contacts l6 and ll of each of the two sets are engaged the contacts of the third set remain disengaged. However, when the ear phone 2| of the third set is removed from its hook l8 the contacts l6 and H of the third set will engage thus completing the signal circuit through the magnets I4. Magnets 14 being thus energized the armatures I0 are caused to move downwardly against the action of springs I2 for moving the slides 8 downwardly to position the legends Not private opposite the windows 1 of the sets so that each party will then know that more than two of the phones are in use and that consequently a party other than the one intended is listening in.

As suggested in Figures '7 and 8 instead of providing a signal casing as an addition to the subscribers set a sight window 22 may be provided at any suitable location in a wall of the set as shown in Figure 7. Suitably provided at the inner side of the wall in an operative position to the sight window 22 will be suitable guides or the like for accommodating a slide plate 23 having a shank or bar 24 associated therewith for connecting the plate 23 with an armature corresponding to the armature hereinbefore referred to. Plate 23 in the lower portion thereof may be provided with a white spot or bulls eye 25 that is normally disposed opposite the sight window 22, and above the bulls eye 25 with a bulls eye 26 of any suitable color as, for example, red, and which bulls eye upon energization of the signal magnet will be brought into position opposite the window 22 for indicating to the user of the phone that a party is listening in contrary to the wishes of the user.

It is thought that a full understanding of the construction, utility and advantages of an invention of this character will be had without a more detailed description.

Having thus described the invention what is claimed as new is:

1. For use in connection with a three subscriber station telephone system for visually indicating inter-connected subscriber stations of the system; a signaling device comprising a battery circuit, an electro-magnet and a normally open switch for said magnet arranged in said circuit for each subscriber station, a visual shiftable signal element for each subscriber station, a movable armature for said electro-magnet connected with said visual signal element, and the switch for the magnet being so arranged relative to the receiver hook of the associated subscribers station as to be engaged by said receiver hook for closing said switch incidental to a removal of the receiver from the hook whereby when the receivers of all of three subscriber stations in the system are removed from said hooks the battery circuit will be completely closed for energizing the magnet of each subscriber station and thereby cause a shifting of the visual signalling element of each station to a position indicating that the receivers of all the subscribers stations in the telephone system have been lifted from their respective hooks.

2. For use in conjunction with a three subscriber station telephone system for visually indicating interconnected subscriber stations, and in combination with the transmitter and receiver hook of each subscriber station, a visual signal element slidably mounted on the transmitter casing of the subscriber set, means for slidably supporting said signal element on said transmitter casing, an electro magnet fixedly mounted in said transmitter casing, an armature complemental to said magnet pivotally mounted within said transmitter casing, an operating connection between said armature and said visual signal element, a normally opened switch mounted in said transmitter casing and including a pair of normally spaced apart contacts insulated from said transmitter casing, and the receiver hook of said subscribers set having means associated therewith for engaging said contacts incidental to an upward swinging movement of the receiver hook subsequent to the removal of the receiver from said hook, and a battery circuit including the electro magnet and the contacts of the respective switches; said battery circuit being closed only upon removal from the receiver hooks of the receivers of all three subscriber sets in the system for energizing the electro magnets to thereby attract the armatures complemental thereto and cause a shifting of said signal elements to a position indicating that the receivers have been lifted from the receiver hooks of all three subscriber stations in the system; and each of said signal elements having two separate and distinguishable indicium thereon, one indicium indicating that the telephone system in which the subscriber sets are embodied is clear, and the other indicium indicating the fact that the subscriber sets in the system are interconnected.

RICHARD H. J. SCI-IOEPPE. 

